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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Jaká existuje podobnost v dynamice přirozených temeprátních lesů severní a jižní polokoule? Případová studie porostů s dominancí Fagus sylvatica L. (Evropa) a Nothofagus spp. (Jižní Amerika)

Ehrenbergerová, Lenka January 2010 (has links)
No description available.
62

Psychological processes of change in adolescents in a residential treatment setting

Swales, Michaela A. January 1996 (has links)
Recent evidence indicates that the proportion of young people developing significant psychosocial problems is increasing (Rutter, 1995). This thesis focuses upon a small percentage of the growing number of adolescents who experience significant psychopathology; adolescents admitted to a regional inpatient psychiatric unit. Chapter 1 provides the theoretical background to the thesis; reviewing the literature on both the methodology and outcome of studies conducted with adolescents in inpatient adolescent psychiatric services. It suggests that future investigations take account of the practical impossibility of conducting high quality, standard double-blind control trials in such settings and outlines four empirical alternatives to such designs; evaluation of components of the therapy employed in residential settings; the use of problem-oriented case records; prediction of outcome across time; investigating the reasons for the effectiveness of established predictors of outcome. The next four chapters describe a series of studies utilising the last three of these suggested approaches in a cohort of adolescents admitted to a regional psychiatric unit. Chapter 2 is a cross-sectional study describing the sample upon which the remainder of the thesis is based. It focuses principally upon describing the psychopathology of the adolescents from three perspectives; that of the adolescent, their parents and the therapeutic team. It examines the interrelationships between mood, behaviour and family functioning. Chapter 3 describes the results of an investigation into the relationships between selfesteem, autobiographical memory, attributional style, social problem-solving and the experience of depression and hopelessness. Chapter 4 examines the clinical effectiveness of the treatment at the unit as assessed by problem severity as rated by adolescents and their parents and standardised measures of mood and self-esteem. Chapter 5 examines to what extent outcome can be predicted on the basis of initial problem severity, mood and cognitive style (autobiographical memory, attributional stye, problem-solving and selfesteem). Each chapter is written as a separate paper with abstract, literature review, method, results and discussion; however, reference to the overall findings is made throughout for ease of reading. The final chapter draws together themes from the whole thesis and discusses the psychological processes which mediate change during the adolescent treatment programme described here. It concludes that the cognitive and meta-cognitive processes which mediate change are best understood as related to internal working models derived from attachment experiences. A model for understanding individual variation in these processes is outlined and strategies for testing the proposed model are advanced.
63

Biodiversity in playa wetlands in relation to watershed disturbance

Malone, Willow Elaine Anna January 1900 (has links)
Master of Science / Department of Biology / David A. Haukos / Playa wetlands are unique ecological systems crucial to the ecology of the western Great Plains of North America. Playas offer a variety of ecological goods and services: flood water retention; water quality improvement; habitat for a distinctive assemblage of resident and migratory biota; and primary recharge points for the Ogallala Aquifer. The major threat to the function of playas is caused by watershed disturbance and habitat loss, primarily through sediment accumulation that decreases playa hydroperiod, density, and size. Previous research focused on playas in the Southern High Plains in Texas and the Rainwater Basin of Nebraska, with little playa studies located in the Central Great Plains. My objectives were to (1) identify the number and level of functionality of existing playas in the Smoky Hill River watershed, (2) determine the relative contribution of playas to the biodiversity of the landscape and influences from watershed disturbance levels, and (3) assess relationships among avian community composition and environmental variables through a canonical correlation analysis (CCA). To assess playa functionality, I randomly selected 20% of the 3,310 historical playas in the watershed and confirmed playa presence and anthropogenic modifications through imagery analysis (n = 608). To achieve the last two objectives, I conducted breeding bird surveys using point counts in >25 playas with paired, nonplaya sites. I recorded avian relative abundance and species richness. Plant species occurrence was detected using step-point methods along transects. Species diversity was derived using Simpson’s index. Approximately 22% of playas have been lost from the landscape. Of the remaining playas, only 3.15% were not affected by anthropogenic influences. Playas contribute greater than 40% and 16% greater avian species richness and diversity to the surrounding landscape, respectively. Playas located in grassland watersheds had a 63% and 35% greater avian species richness and diversity, as well as 57% and 66% greater floral species richness and diversity than playas located in croplands, respectively. CCA results identify playa soil moisture and watershed disturbance as significant influences to the playa avian community. It is important to reduce watershed disturbance and anthropogenic influence on playas to maintain biodiversity at local, regional, and continental scales.
64

Současná dynamika krajiny NP Šumava / Recent landscape dynamics of the Šumava NP

Janík, Tomáš January 2016 (has links)
The disturbances are processes, which change the landscape (Bengstsson et al., 2003). In Central European mountains spruce forest, windthrows and subsequent bark beetle (Ips typographus) outbreaks are the most important (Bengstsson et al., 2003; Brůna, 2013; Čada, 2013; Fischer et al., 2002; Matějka, 2013) This scenario was taking place in the study area - the Šumava National Park between 2006 and 2012. The objective was to analyse changes in the land cover caused by the disturbances. The land cover flows were used. The Land cover flows describe changes within land cover types: the area of change from one type into another (Martinez-Fernandez et al., 2015). Layers of the land cover for each year were created; they show the changes mostly in forested landscape. These fourteen-land cover types layers were input into analysis in the Land change modeler for ArcGIS (Clark Labs, 2015). The most important land cover flows were set and further analysis of evaluation in five spatial frames (Physical - geographical typology, Aspect, Elevation, Ecological conditions, Non-intervention and intervention management) were undergone for deeper knowledge about spatial factors of distribution. The Kyrill windthrow in 2007 caused a creation of windfalls (4.73 km2 ), predominantly made from damaged forested area (3.07...
65

Neurosensory disturbance after bilateral sagittal split osteotomy

Ylikontiola, L. (Leena) 23 August 2002 (has links)
Abstract Neurosensory disturbance is a common complication of bilateral sagittal split osteotomy (BSSO). This study focuses on the evaluation of factors affecting neurosensory disturbance after BSSO. Furthermore, the study focuses on the measurement of neurosensory disturbance with easily available bedside tests, not only on evaluating the state of sensory disturbance at each follow-up, but also on predicting the potential for recovery. Moreover, panoramic radiography, computerized tomography (CT) and conventional spiral tomography are assessed on locating the mandibular canal. The study was carried out involving a total of 50 patients undergoing BSSO for the correction of mandibular deficiency. In addition, 20 voluntary healthy students participated in this study. Questionnaires, a battery of neurosensory tests and preoperative imaging of the mandibular canal were used. A high incidence of neurosensory disturbance of the lower lip and chin was found after BSSO. However, recovery of sensation occurred with increasing frequency during the follow-up, and after one year sensation of the lower lip and chin returned to the presurgical situation in most patients. A prolonged neurosensory disturbance was more frequent in older patients, in large surgical movements of the mandible and in cases where the inferior alveolar nerve was manipulated during surgery. The bedside tests used in this study correlated well with the patients' subjective evaluation of neurosensory disturbance, and the repeatability of these tests was good. Furthermore, the sensibility testing of the mandibular teeth correlated well with the other tests and patient's subjective evaluation. Four days after surgery, sensibility testing of the mandibular teeth was an efficient test alone to predict the recovery from neurosensory disturbance. On radiographic imaging, the risk for neurosensory disturbance after BSSO could not be predicted from the panoramic radiograph. Before BSSO, CT was the best method to visualize the buccolingual location of the mandibular canal. After BSSO, a clinical follow-up using a battery of mechano- and nociceptive tests in the examination of sensation of the lower lip and chin, sensibility testing of the teeth, and subjective evaluation is needed. CT should be a part of treatment planning of the patients with thin rami or severe asymmetries of the mandible.
66

Hurry up and wait: life cycle and distribution of an intermittent stream specialist (Mesocapnia arizonensis)

Bogan, Michael T. 12 1900 (has links)
Species inhabiting intermittent streams must have life-history traits that confer resistance or resilience to flow cessation or drying. However, we lack basic life-history information for most aquatic invertebrate species, especially those from intermittent streams. I documented the life cycle and distribution of an unusual winter stonefly species, Mesocapnia arizonensis (Capniidae). The species was first described from 6 localities in 1969, but its natural history remained enigmatic. I surveyed >90 streams across the southwestern USA, documented the life cycle of M. arizonensis at 1 locality, and experimentally rehydrated dry streambed sediment in search of dormant stoneflies at another locality. Field surveys expanded the number of localities from 22 to 98, most of which were intermittent with flow durations as brief as 3 mo/y, and extended the known range of the species by 800 km. Nymphs were abundant within days of flow resumption, grew rapidly as a single cohort, and started emerging as adults 42 d after flow resumed. The brief appearance of a 2(nd) cohort of tiny nymphs 1 mo before the stream dried indicates direct hatching of at least some eggs. I failed to find dormant stoneflies in the top 30 cm of dry stream sediment, suggesting that M. arizonensis undergoes dormancy deep in the substrate, putting it safely out of reach of scouring summer floods that occur between favorable winter seasons. The remarkable ability of M. arizonensis to survive in short-flow duration streams and to endure multiple consecutive dry years, suggests that the species is well prepared for the drier climatic conditions predicted to occur across its range.
67

The effects of anthropogenic disturbance upon African penguin colonies

Miller, Rebecca Jane January 2020 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) - MSc (Biodiv and Cons Biol) / African penguin (Spheniscus demersus) mainland colonies are a popular tourist attraction in the Western Cape of South Africa. The African penguin population is in decline and the species is listed as endangered on the International Union for the Conservation of Nature (IUCN) Red List. This thesis aimed to investigate the impact of ecotourism upon African penguin colonies by comparing two colonies of differing levels of tourist visitation in the Western Cape in 2017. The high visitation colony is a mainland colony where ecotourism activities take place (Stony Point), and the low visitation colony is an island colony where ecotourism does not occur (Robben Island). As well as inter-colony comparisons, nests at the high visitation colony within areas of differing exposure levels were also compared.
68

Vliv lesních disturbancí na dynamiku odtoku v oblasti centrální Šumavy / Impact of forest disturbances on the runoff in the central Sumava Mts.

Bartůňková, Kristýna January 2011 (has links)
Impact of forrest disturbance on the runoff in the central Šumava Mts. ABSTRACT The diploma thesis deals with the influence of forest disturbance, as for example wind and bark beetle calamities, to the runoff characteristics in the central Šumava Mountains. The analysis of five precipitation events and their runoff responses was applied to seven small experimental catchments with different stage of disturbance. Studied catchments were catchments fo Tmavý, Roklanský, Březnický, Javoří, Cikánský, Černohorský potok and Antýgl. Chosen precipitation events belong to the years 2009 and 2010 and to warm half year, when no snow cover can influence the runoff. Similarity of catchments was established by cluster analysis. For comparison of the reaction of single catchments to the same precipitation event was used simple comparison of precipitation and runoff data and waves. Key words: forest disturbance, central Šumava Mountains, rainfall-flow conditions, cluster analysis
69

National Leadership for Children and Youth With Serious Emotional Disturbance: Progress and Prospects

Coutinho, Martha J., Denny, R. Kenton 01 January 1996 (has links)
Despite the federal mandate to identify and provide appropriate educational and related services to children and youth with serious emotional disturbance (SED), the national profile portrays exceptionally low rates of identification; unacceptably low rates of school completion; high rates of placement in segregated environments; evidence that economic and demographic factors substantially affect identification, placement, and school completion; and a mixed, although mostly discouraging picture of outcomes after leaving the educational system. Recent national leadership, comprised of strategic planning, research, and demonstration initiatives has attained considerable momentum and is intended to improve outcomes for children with SED. Significant changes are anticipated as a result of the upcoming reauthorization of the statute governing special education and related services. These changes reflect a 20 year perspective regarding the benefits and shortcomings of current eligibility criteria and discretionary initiatives for improving outcomes for children with disabilities. The manner in which these changes may affect prospects for better serving children with SED is discussed.
70

Collective Behavior and Campus Public Order Policing: A Qualitative Case Study of Mixed-Issue Campus Disturbances at Three Midwest Public Universities

Sigler, Todd Dee 01 December 2011 (has links) (PDF)
AN ABSTRACT OF THE DISSERTATION OF Todd D. Sigler, for the Doctor of Philosophy degree in Education Administration Higher Education, presented on October 28, 2011, at Southern Illinois University Carbondale. TITLE: COLLECTIVE BEHAVIOR AND CAMPUS PUBLIC ORDER POLICING: A QUALITATIVE STUDY OF MIXED-ISSUE CAMPUS DISTURBANCES AT THREE MIDWEST PUBLIC UNIVERSITIES MAJOR PROFESSOR: Dr. Kathryn Ann Hytten The purpose of this qualitative study analyzed mixed-issue campus disturbance events at three similar public universities located in the Midwest region of the United States. Using a case study research design, the analysis draws from interviews conducted with campus police officers employed at the selected institutions assigned to work one or more disturbances during the last decade. A related purpose analyzed the element of space/location and territoriality where these disturbances occurred, including an assessment of the value and meaning of space to the police and how police use space to achieve public order maintenance objectives. As the primary social control agent, the police - through their interface with crowd participants - can influence positive or negative relationships that subsequently impact disturbance outcomes. The research methodology incorporated naturalistic qualitative methods including: (1) one-on-one interviews of 15 campus police officers - both front-line police officers and command officers divided among three campuses; (2) open source public documents such as task force reports and newspaper articles; and (3) closed-source documents, such as unpublished pre- and post-action reports completed by law enforcement or campus administration. Finally, I conducted field research observations of the disturbance locations combined with my own experience in campus law enforcement. Among some of the important findings are the importance of officer experience, consistent and recent training for officers in both traditional crowd control tactics, as well as crowd management skills, especially communication (accomplished through techniques such as dialogue policing and social media technology to recognize and mitigate triggering behaviors on both sides. Additional public order policing tactics include recognizing the importance of territoriality and the value of mitigating tactics such as crowd combing, and controlling space to reduce density. This study will support law enforcement officials in higher education with planning, developing and responding proactively to disturbances using public order policing strategies suitable for campus communities. Special emphasis is placed on the elaborated social identity model and the negotiated management model to explain police and crowd behaviors. Of value to crowd management practitioners is the critical need to interface crowd theory with practical public order policing techniques to develop an effective response.

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